In prior art machines for the checking of printed circuits are known.
These machines generally are endowed of a board or bed that bears a plurality of electrically conductive needles, on which is placed the printed circuit card and by suitably activating the electric conductivity among the different needles and by taking the respective measurings it is possible to check whether or not the printed circuit has some defects.
Obviously for such check it is necessary for the needles to contact the printed circuit in the suitable position. As the printed circuits are very different, it is necessary to apply over the base needle board, an adaptation board that comprises the same needles but displaced in a different way according to the printed circuit to be checked.
The drawback of this solution is in the limits of the machine and in the possibility of checking only the printed circuits for which are available corresponding adapters or adapting boards.
Requiring as many adapting boards as are the cards with different printed circuits to be checked.
Furthermore it is known that the surfaces of the circuits are not always coplanar, wherefore it is not always ensured a suitable and
vacuum-actuated means included within the compression means and connected to the bottom-side bed-of-nails test probe array for locking down said DUT during a test and for generating said pushrod force for driving the bommo-side bed-of-nails test probe array into electrical contact with said plurality of test points on said second side of said DUT. PA1 are used at least two coplanar needle boards one adjacent to the other, and PA1 one board is made movable independently from the other, and PA1 the respective card to be checked is made movable independently from at least two boards or vice-versa. PA1 a topside, door-mounted array of spring-loaded electrical probes for electrical connection with a first side of a device-under-test (DUT); PA1 a bommo-side bed-of-nails test probe array for electrically contacting a plurality of testpoints on a second side of said DUT opposite to said first side; PA1 compressing means mechanically articulated to the topside, doors mounted array of spring-loaded contacts and fixed to the bottom-side bed-of-nails test probe array for clamping said DUT with; PA1 a lever mechanically connected to the compressing means and articulated to the array of spring-loaded electrical probes and having means for receiving a pushrod force of a first direction perpendicular to a plane including the array of spring-loaded electrical probes and for translating said pushrod force to drive said array of spring-loaded electrical probes independently articulated within the compressing means in a second direction opposite to said first direction and into perpendicular electrical contact with a plurality of test points on said first side of said DUT; any position of the circuit leading end and to activate an opposed needle of the opposed board, which thanks to the mobility, even of said opposed board can reach any determined circuit end point to be tested independently of its position, place and shape. PA1 when the printed circuit opposed points to be checked lie one under the first and the other under the second board, and do not coincide with the sound needles, it is sufficient to move both the first and the second board (or move also the card) to position them in exact correspondence with the opposed points to be checked; PA1 when the two printed circuit opposed points to be checked are so close to be covered by just one board, it is sufficient to move the card to be checked with said circuit to an exactly intermediate position between said two boards (or vice-versa to move both said boards), so that one point of the circuit lies under the first plate and the other lies under the second board, and then by moving both of them it will be possible to make perfectly coincide said two points with one respective needle from each of said two boards.